Refractory materials have often been utilized in order to provide decorative displays. Such materials may be of a natural origin such as, for example, quartz crystals, or may be comprised of synthesized compounds demonstrating desired refractory properties. All such materials, regardless of composition, require a source of light to be refracted into a decorative spectrum of color. When the light source utilized is fixed in position, the refractory material may be rotated so as to provide an optimal angle of incidence with such a source, as well as to provide both movement and variety in the resultant mufti-color displays.
In the past, electric motors have been utilized to rotate refractory materials in order to provide a multi-colored display which generates light patterns of varying colors. For example, U.S. Pat. No. 4,764,850 discloses a device wherein an electric motor, powered by means of a photovoltaic cell, is utilized to rotate a generally diamond shaped leaded glass crystal. The crystal is selected to demonstrate a tapered lower end and different-sized facets so as to provide different angles for refraction of sunlight striking the crystal. Since the crystal is radially symmetric—as opposed to having a flattened or otherwise asymmetric cross-sectional conformation—the crystal continuously rotates adjacent facets into incident light.
The crystal utilized in the '850 patent is mounted upon a cup shaped receptacle which, in turn, is mounted upon a drive shaft extending above the device housing. When the device is exposed to sunlight, the diamond shaped crystal is rotated so as to refract the light into a “series of spots or patterns of different colors or hues across the walls or ceiling of the room, thus forming an aesthetically appealing display.” (col. 3, lines 41–43 of the '850 patent). The solar powered motor drive unit described in the '850 patent provides, by means of a gear drive system, rotation of the tapered crystal at a speed of from 2 to 3 rpm so that adjacent facets of the tapered crystal are repeatedly exposed to incident light. However, the radially symmetric shape of the disclosed crystal would not be expected to provide for effective movement of a particular projection, such as, for example, a rainbow, across a wall or other surface due to the fact that the radially symmetry of the crystals utilized therein continuously repeats the same angles of incidence to the light source.
The solar-powered crystal display disclosed in the '850 patent utilizes a configuration in which the rotating crystal is mounted above a generally rectangular box having a top, bottom, front, rear, left and right sides. A portion of the top of the rectangular housing defines an inclined plane for mounting of a photovoltaic panel. The housing demonstrates a relatively low profile with substantially greater depth and length dimensions as compared to height. The drive motor and the output shaft of the '850 device are horizontally aligned in that they are mounted and positioned in a parallel relation to the top and bottom housing. The output shaft of the '850 motor utilizes a worm gear in order to engage a drive gear positioned upon the vertically aligned crystal drive shaft. Therefore, the '850 device presents a rather bulky, horizontally aligned housing upon which a vertically aligned crystal is rotated. Although such a design may have some utility in providing a stable base for placement upon, for example, a shelf or table, no other means is provided so as to enable optimal placement of said device upon a window. Certainly, the 3 dimensional configuration of the '850 device makes placement directly against a window—the typical portal for ambient light—rather cumbersome. It would be highly advantageous if a crystal display device could be provided demonstrating a substantially reduced depth—a flattened profile—as well as a means of affixing same directly to a window with minimum interference with the operation of blinds, shades or other window light control means.